Electrostatically controlled friction coupling

Claim 1

A FRICTION COUPLING COMPRISING FIRST AND SECOND MEMBERS RELATIVELY ROTATABLE ABOUT AN AXIS, A LAYER OF A DIELECTRIC MATERIAL HAVING HIGH ELECTRICAL RESISTANCE FIXED TO ONE OF SAID MEMBERS AND PRESENTING A PRECISELY FLAT RIGID SURFACE DISPOSED IN A PLANE SUBSTANTIALLY RADIAL TO THE AXIS OF RELATIVE ROTATION, A FLAT THIN FLEXIBLE DESK OF RESILIENT METAL, MEANS FOR FIXING THE CENTRAL PORTION OF SAID DISK TO THE OTHER OF SAID MEMBERS SO AS TO DISPOSE THE DISK RADIALLY OF SAID AXIS WITH A METAL SURFACE OPPOSED TO AND SUBSTANTIALLY COEXTENSIVE WITH SAID RIGID SURFACE AND WITH AN AXIAL POSITION PROVIDING CLOSE PROXIMITY OF, BUT WHICH NORMALLY PRECLUDES SUBSTANTIAL RUBBING CONTACT AND HEAT GENERATING AT SUCH SURFACES, AND DISK BEING OF SUBSTANTIALLY UNIFORM AND EXTREMELY SMALL THICKNESS OVER ITS ENTIRE PORTION WHICH IS COEXTENSIVE WITH SAID RIGID SURFACE AND BEING FREELY FLEXIBLE INTO FULL AND INTIMATE FRICTIONAL GRIPPING CONTACT WITH SUCH RIGID SURFACE, AND MEANS FOR SELECTIVELY APPLYING A VOLTAGE BETWEEN SAID DISK AND DIELECTRIC MATERIAL TO CREATE AN ELECTRIC FIELD WHICH FLEXES THE DISK INTO FULL FACE, CONFORMING ENGAGEMENT WITH SAID RIGID SURFACE, THEREBY TO ENGAGE THE COUPLING.